Environmentally, radionuclides are used to trace and analyse pollutants, to study the movement of surface water, and to measure water runoffs from rain and snow, as well as the flow rates of streams and rivers.

Secondary radionuclides are radiogenic isotopes derived from the decay of primordial radionuclides.

Environmentally, radionuclides are used to trace and analyze pollutants, to study the movement of surface water, and to measure water runoffs from rain and snow, as well as the flow rates of streams and rivers.

Radionuclides are present in the living and non-living components of each aquatic environment, both natural radionuclides of primordial and cosmogenic origin, and artificial radionuclides from nuclear and non-nuclear industrial wastes, accidental releases and nuclear weapons fallout (see sources in Chapter 1).

Radionuclide species in solution may depend on the ionic composition and ionic strength of the water, the presence of organic ligands, the redox state (Eh) and acidity (pH); an important contrast in nuclide behaviour is thus observed between aerobic and anaerobic waters.

The radionuclide flux to the sediment surface and, hence, the radionuclide inventory in the deposits depends on both the activity concentration, which is a function of grain size, and the mean sedimentation rate.

The primary intent is to demonstrate how the half-life of a radionuclide can be used in practical ways to "fingerprint" radioactive materials, to "date" organic materials, to estimate the age of the earth, and to optimize the medical benefits of radionuclide usage.

Remember that a radionuclide represents an element with a particular combination of protons and neutrons (nucleons) in the nucleus of the atom.

Radionuclides such as Tc-99m, with a half-life of six (6) hours, are routinely used in bone scans because the medical objective is successfully reached while the amount of radioactivity diminishes rapidly.

Since each nuclear medicine radionuclide has a unique gamma-ray emission energy spectrum, and since the energy of a gamma-ray is detected in a gamma-camera by the brightness of the scintillation associated with an event, gamma-cameras employ energy 'windows' to gate or limit the imaging process to gamma-ray events of particular energies.

This means that a tiny amount of a radioactive substance, called a radionuclide (radiopharmaceutical or radioactive tracer), is used during the procedure to assist in the examination of the tissue under study.

A radionuclide (usually technetium) will be injected into an arm vein to “tag” the blood cells so their progress through the heart can be traced with a scanner.

The amount of the radionuclide injected into your vein for the procedure is small enough that there is no need for precautions against radioactive exposure.

At low radionuclide concentrations, solid wastes can be disposed of in a municipal landfill or a physical barrier.

In deriving the IRALFs from the post-accident radiation dose limits established by radiation protection authorities, the Consultation agreed that the levels should provide broad margins of safety and be applied as widely as possible to minimize unnecessary interruptions to international trade to help protect the welfare of otherwise affected agricultural and/or fisheries communities.

It is possible that pain relief is caused by a cytotoxic effect on normal bone cells, thereby inhibiting the release of pain mediators.

The fourth GEOTRAP workshop, "Confidence in Models of Radionuclide Transport for Site-specific Performance Assessments" was held in June 1999.

The third GEOTRAP workshop, "Characterisation of Water-Conducting Features and their Representation in Models of Radionuclide Migration" investigated how water-conducting features can determine the rate of radionuclide release from the near-field to the far-field, the rate at which radionuclides can migrate with flowing groundwater, and the degree of retention in the geosphere.

It provided an overview of on-going and planned work in the study of radionuclide transport phenomena and the characterisation of relevant properties of the geologic media.

These will allow the identification of atmospheric explosions, as well as underground or underwater explosions that are close enough to the surface to vent gases and / or particulate debris into the atmosphere.

The radionuclide network also provides information to aid in the detection, location and characterization of events detected by stations of the seismic, infrasound or hydroacoustic networks, either individually or in combination.

EPA, other federal agencies, states and contractors who are responsible for the identification, characterization and remediation of sites contaminated with radioactive materials use radionuclide slope factors in risk assesments to calculate potential risks to the general public.

EPA's Office of Radiation and Indoor Air (ORIA) calculates radionuclide slope factors to assist risk assessors with risk-related evaluations and decision-making at various stages of the remediation process.

This update of the HEAST for radionuclides incorporates all new values, based on Federal Guidance Report No. 13 (1), which was developed by EPA's Office of Radiation and Indoor Air (ORIA).

Furthermore, an incident resulting in release of radionuclides from one of the nuclear facilities addressed in the 1998 FDA document would likely result in the release of the same radionuclides regardless of whether the cause of the release was accidental or intentional.

The radionuclides in the Cs group are deposited throughout the body and are beta-particle and gamma-ray emitters.

The radionuclides Ru-103 and Ru-106 are chemically identical, are deposited throughout the body, and are beta-particle and gamma-ray emitters.

Do radionuclide and echocardiographic techniques give a universal cut off value for left ventricular ejection fraction that can be used to select patients for treatment with ACE inhibitors after myocardial infarction.

The reproducibility of radionuclide angiographic measurements of left ventricular function in normal subjects at rest and during exercise.

Comparison of different echocardiographic methods with radionuclide imaging for measuring left ventricular ejection fraction during acute myocardial infarction treated by thrombolytic therapy.

The overall aim of the project was to examine the retardation of radionuclides in this shear zone.

These models were then tested by carefully adding safety-relevant radionuclides to the shear zone and observing their in situ retardation behaviour.

Diffusion of radionuclides occurs when the radionuclides move from the main flow path into the pore spaces in the granodiorite around the flow path (the flow path being the open area of the shear zone - see above).

A new treatment for prostate cancer may provide a distinct advantage over other conventional protocols and induce actual regression of the disease - not just relief from bone pain or a limited control of the disease, according to a study by Italian researchers released at Society of Nuclear Medicine's 53rd Annual Meeting in San Diego.

More than 234,000 men in the United States will be diagnosed with prostate cancer this year, and more than 27,000 will die of the disease, which is the second leading cause of cancer death in men.